1. Field of the Invention
This invention relates to an apparatus for inspecting the operation of a number of integrated circuit devices, such as ICs or LSIs, mounted on a printed circuit board. More particularly, it relates to such apparatus whereby signals can be taken out simultaneously at all of the lead terminals of an integral circuit device for more prompt and efficient inspecting operation.
2. Description of the Prior Art
In inspecting the operation of integrated circuit devices, such as ICs or LSIs, mounted on a printed circuit board, so-called IC test clips are generally employed. The test clip is mounted on the integrated circuit device on the printed circuit board from above and a contact portion electrically connected with a contact pin projecting from the upper side of the clip is brought into pressure contact with the lead terminal of the IC device. The operation of the circuit mounted on the printed circuit board is inspected with a probe such as an oscilloscope electrically contacted with the contact pin.
FIG. 10 shows an example of the IC test clip of a so-called clothespeg type having body portions 50, 50 pivotally connected to each other by a pivot shaft 51. These body portions are biased by a spring 52 so that the lower ends of the body portions 50, 50 will be urged towards each other. Contact pins 53 projected from the upper ends of the body portions 50, 50 are electrically connected with the contact portions 54 at the lower ends of the body portions 50, 50. When attaching the IC test clip to the integrated circuit device, the lower ends of the body portions 50, 50 are extended apart against the bias of the spring 52. The test clip is attached to the device from above so that the latter is clamped between the extended apart lower portions. This causes the contact portions 54 to be pressure contacted with the lead terminals of the integrated circuit device.
FIG. 11 shows another example of the IC test clip. This test clip includes a pair of body portions 56, 56 pivotally connected to each other by a pivot shaft 55 and contact pins 57, 57 projecting from the upper ends of these body portion and electrically connected with contact portions 58 at the lower ends of the body portions 56, 56. When attaching the IC test clip to an integrated circuit device, a slide member 59 slidably mounted about the perimeter of the body portions 56, 56 is thrusted down until the contact portion 58 are brought into pressure contact with the lead terminals of the integrated circuit device.
In the operation of these IC test clips shown in FIGS. 10 and 11, the operation of the circuit device is inspected with the signals being taken out one at a time as the probe such as the oscilloscope is sequentially contacted with the contact pins 53 or 57.
When the inspection is performed with the use of a measuring unit such as a logic analyzer and with concurrent intake and processing of plural signals, end clips of a multiple probe may be engaged with plural contact pins 53 or 57 of the IC test clip for signal intake and processing. Alternately, a cable may be temporarily wound about or soldered to pins 53 or 57 with the other ends of the cable being connected to the measuring unit.
However, when the inspection is performed in this manner with concurrent processing of plural input signals with electrical connection being made to a plurality of lead terminals of the integrated circuit device, the aforementioned IC test clips adapted for sequentially taking out signals one at a time need be used sequentially for each of these lead terminals, so that the inspecting operation cannot be performed with higher inspecting efficiency.